Can miles truly separate you from friends... If you want to be with someone you love, aren't you already there?
I live for Pilates reformer class. I go at least three times a week. It's a great way to lengthen your muscles, stretch, and kind of relax your mind.
It's a question of spreading the available energy, aerobic and anaerobic, evenly over four minutes. If you run one part too fast, you pay a price. If you run another part more slowly your overall time is slower.